#include <iostream>
#include <fstream>

using namespace std;

const char iname[] = "numarare.in";
const char oname[] = "numarare.out";
const int nmax = 100005;

ifstream fin(iname);
ofstream fout(oname);

int N, A[nmax], i, j, k, sol;

int main()
{
	fin >> N;
	for(i = 1; i <= N; i ++)
		fin >> A[i];
	for(i = 1; i <= N; i ++)
		for(j = i + 1; j <= N; j ++)
			for(k = 0; k <= j; k ++)
			{
				if(A[i + k] + A[j + k] != A[i + k - 1] + A[j - k + 1])
					continue;
				sol ++;
			}
	fout << sol;
	return 0;
}